uprobes/tracing: Kill the pointless task_pt_regs() calls

uprobe_trace_func() and uprobe_perf_func() do not need task_pt_regs(),
we already have "struct pt_regs *regs".

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Tested-by: Anton Arapov <anton@redhat.com>

kernel/trace/trace_uprobe.c

@@ -507,7 +507,7 @@ static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs)
 		return 0;
 
 	entry = ring_buffer_event_data(event);
-	entry->ip = instruction_pointer(task_pt_regs(current));
+	entry->ip = instruction_pointer(regs);
 	data = (u8 *)&entry[1];
 	for (i = 0; i < tu->nr_args; i++)
 		call_fetch(&tu->args[i].fetch, regs, data + tu->args[i].offset);
@@ -777,7 +777,7 @@ static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs)
 	if (!entry)
 		goto out;
 
-	entry->ip = instruction_pointer(task_pt_regs(current));
+	entry->ip = instruction_pointer(regs);
 	data = (u8 *)&entry[1];
 	for (i = 0; i < tu->nr_args; i++)
 		call_fetch(&tu->args[i].fetch, regs, data + tu->args[i].offset);